<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>计算器</title>
</head>
<body>
    <form action="/calc/sum" method="post" class="sum">
        <h1>web计算器</h1>
        <span>数字1：</span><input name="num1" type="text"><br>
        <span>数字2：</span><input name="num2" type="text"><br>
        <input type="submit" value="点击相加">
    </form>
</body>
</html>